A belt of a conveyor is conventionally supported between its ends by a plurality of carriers. Each carrier typically includes a frame extending transversely to the conveyor belt and journals generally three idler rolls in an end-facing-end relationship. Generally, the intermediate idler roll is disposed in a horizontal position while the outer two idler rolls are disposed at an upwardly inclined angled relationship to a horizontal plane to give the conveyor belt a trough-like shape for the purpose of keeping a load centered on the conveyor belt.
The idler rolls typically have bearing assemblies, which are interposed between a rotating roller shell and a stationary shaft. The bearing assemblies commonly include ball bearings as the rolling elements. However, it is also known for the bearing assemblies to have tapered roller bearings as the rolling elements because the tapered roller bearings can provide twice the minimum life of ordinary ball bearings. However, tapered roller bearing elements require precise axial clearance settings. It is known to secure bearing assemblies, and particularly tapered roller bearings assemblies, with threaded assemblies and/or snap rings with compensating washers to account for manufacturing variations.
Also, it is generally known to press various bearing assemblies onto various shafts. This is a rather simple and low-cost approach. The long shaft lengths of idler rolls, however, have made press fitting roller bearing assemblies directly onto a shaft impractical because of the precise axial clearance seating required versus shaft flexibility and compressibility. As such, there is an increased problem with obtaining and maintaining axial positioning of bearing assemblies.
It is further known to machine-cut rectangular grooves into shafts for application of retaining rings to secure idler roll assemblies in proper location. As such, it is to be appreciated that several processing steps are needed. Reference is hereby made to U.S. Pat. Nos. 6,287,014 and 6,385,849, which each shown the use of ring grooves cut in shafts for retaining bearing assemblies of idler rolls.
Accordingly, there is a need for an idler bearing assembly having a different structure and thus having a different manufacturing process.